钱塘江中游水生昆虫群落功能多样性对土地利用变化的响应

基于11个反映水生昆虫生活史、对外界抵抗力和生理特征的生物学性状，应用目前国际上通用的fourth-corner统计方法，系统研究了浙江省钱塘江中游流域水生昆虫功能多样性对土地利用变化的响应.结果表明： 部分生物学性状对土地利用变化敏感，且其随人类干扰强度的变化所发生的改变与预期吻合，其最大个体长度逐渐下降，呼吸方式从以鳃呼吸为主转变为以表皮呼吸为主，掘穴者数量显著增加.参照点的功能多样性指数(Rao值)显著高于干扰点(P<0.001).说明人类活动引起的土地利用变化导致溪流水质和栖境质量下降，引起群落的变异和对生物性状组成的筛选，最终导致水生昆虫群落功能多样性改变.生物性状及功能多样性是未来评价生态健康的潜在指标.

Responses of functional diversity of aquatic insect community to land use change in middle reach of Qiantang River,East China

Based on the biological traits such as life history, resistance ability against environmental disturbance, and physiological characteristics of aquatic insects, and by using the fourth corner statistical method, this paper studied the responses of the functional diversity of aquatic insect community to land use change in the middle reach of Qiantang River, Zhejiang Province of East China. For the test aquatic insect community, some of its biological traits were sensitive to land use change, and altered along human disturbance gradients as expected. With the increasing intensity of human disturbance, the maximal insect body length decreased gradually, the dominant respiration pattern evolved from gill respiration to tegument respiration, and the abundance of burrowers increased significantly. At the same time, the functional diversity measured as Rao’s quadratic entropy was significantly higher in reference sites than in disturbed sites (P<0.001), demonstrating that the changes in the functional diversity of the aquatic community were mainly induced by the land use change caused by human activities, which resulted in the decline of stream water quality and habitat quality and the variations of aquatic insect community composition and biological traits. The aquatic insect biological traits and functional diversity could be the potentially effective indicators in the stream health assessment in the future.